Blocking isn’t enough. There are multiple reasons I might avoid blocking someone participating in this behavior. For one, they can continue tweeting at you and directing others to harass you, but you won’t be aware. They could be making credible threats that you might need to act on. They could be harassing your followers and friends. In this case, all of those were true.
Your idea about showing the number of times someone has been blocked would turn blocking itself into a potential form of harassment. What’s to prevent malicious users from blocking someone en masse, then pointing to that number as “evidence” that someone is bad or should be avoided?
Yes, banning is the only acceptable solution, for me, in a case like this one. By not banning this user, Twitter allowed the harassment to continue and sent a message that this behavior is acceptable on their platform. By responding by saying that the account wasn’t violating any rules, they were gaslighting me. Yes, the user can probably create another account and continue the behavior, so banning isn’t a catch-all solution.
Some sites/apps take an in-between action sometimes referred to as graylisting or shadow-banning. In this scenario, the user’s content stops appearing, and to other users it seems like the account doesn’t exist — but the user doesn’t know they’ve been banned, and to them it appears as though the site, and their account, are functioning as normal. This can prevent the creation of additional accounts, but has its own pitfalls. It can erode user trust because the site is effectively deceiving people (although yes, these people are ones the site has determined to be bad actors). It’s also possible for a user to discover that this is occurring, which could cause them to escalate in retaliation.
Responding to harassment also isn’t the only approach apps and sites can take. Products can be built in ways that discourage or neutralize harassment in the first place, make it more difficult for harassment and dogpiles to gain traction, etc.